how do I determine whether a python script is imported as module or run as script?

from python docs:

When you run a Python module with

python fibo.py

the code in the module will be
executed, just as if you imported it,
but with the __name__ set to
"__main__". That means that by adding
this code at the end of your module:

if __name__ == '__main__':
    # Running as a script

you can make the file usable as a script as well as an importable module, because the code that parses the command line only runs if the module is executed as the “main” file